Year: 2023
Type: article
Abstract: Continuous variable quantum key distribution (CV-QKD) allows the distribution of symmetric keys in a secure manner. CV-QKD systems can extract keys at its maximum rate when using Gaussian modulation (GM). Nonetheless, GM demands high-capacity random number sources and tends to be very hard to approach in practice. To circumvent these disadvantages, higher-order probabilistic -shaped discrete modulation (DM) can be used. State-of-the-art works compute the key rates of DM-CV-QKD systems considering a fixed value for the reconciliation efficiency and do not take into account the frame error rate (FER) of the system, thus over or under estimating the key rates. In this work, we study the security bounds of CV-QKD systems considering probabilistic shaped DM formats with 256-symbols in the finite-size regime. This accounting for the true value of the reconciliation efficiency, and the FER of the information reconciliation step. Both conventional and hexagonal 256-quadrature amplitude modulation (QAM) constellations yield higher key rates than 256-amplitude and phase shift keying (APSK) constellations, with 256-QAM constellations being indistinguishable in performance with GM for high transmission distances. Minimum signal-to-noise ratio (SNR) values were fixed from a FER analysis through a CV-QKD simulation allowing for key extraction considering different FER levels. Lower FER values are associated with higher SNRs in the system and thus lower achievable transmission distances. Nonetheless, the FER maximizing the extraction key rate is not null. Our results show that the extraction key rate is maximized by SNR adjustment which should have in account both the reconciliation efficiency and the FER.
Source: Journal of Lightwave Technology
Institutions: Instituto de Telecomunicações, University of Aveiro
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,345
Awards: G1167214205, G1578237752, Quantum Enabled Secure Multiparty Computation for Genomic Medicine, G2031848694, G2144570049, G2513729180, Instituto de Nanoestruturas, Nanomodelação e Nanofabricação, G2863610110, Design and Implementation of a Quantum Oblivious Key Distribution Protocol using Continuous Variables, G3343613049, Instituto de Telecomunicações, G3850789590, G3891694003, Instituto de Nanoestruturas, Nanomodelação e Nanofabricação, G491858407, G6329845220, Geração de números primos habilitada por tecnologias quânticas para aplicações criptográficas, G6773135875, G6931834846, Instituto de Nanoestruturas, Nanomodelação e Nanofabricação, Instituto de Telecomunicações, G8911869519
OpenAlex ID: W4378195031